In eight volunteers, gastric emptying rates of both 400 mL of a ready-to-use beverage (A: Nutricia preOp; 50.4 g carbohydrates—mainly polysaccharides; 260 mOsm/kg) and 400 mL over-the-counter fruit-based lemonade (B: Roosvicee Original; 48 g carbohydrates—mainly fruit-associated saccharides; 805 mOsm/kg) were determined scintigraphically (using hepatate Tc-99m) according to a crossover design. Plasma glucose, insulin, C-peptide, glucagon-like peptide (GLP-1), peptide YY, total glucagon, and ghrelin were studied.
Gastric emptying showed no differences in residual volumes. Earlier onset in emptying for beverage A versus B was observed (trend), with significantly higher glucose, insulin, C-peptide, and glucagon responses at 15-90 min. GLP-1 was inversely related to residual volume.
Fruit-based lemonade is a safe alternative for preoperative purposes. It induces a more limited glucose, insulin, and C-peptide response. Later onset in gastric emptying (B versus A: trend), lower glucagon release, and differences in beverage content and osmolarity may have contributed to those differences. Efficient emptying was reflected by early GLP-1 levels.